Staff to freelance

Hello everyone!

I've been working as a staff hack for around three years on a few well-respected paid for local rags and big distribution free titles, as well as making regular paid contributions to daily regionals.
I enjoy my job, work with good people but feel like my chances of progression are becoming slimmer and slimmer as redundancies bite.
I know I'm a good reporter and I care deeply about the job and impact it can have on people's lives.

But....

I really want to work for myself.

What tips can you all offer about making the leap from staff to freelance?
I feel like I could happily cruise along in my present position and watch time roll by, but it just isn't my style.
I'm not afraid of risks, and although I do have financial responsibilities, would be prepared to gamble if I thought I had a good chance of achieving the freedom of self-employment.

I've attended a NUJ freelance course, which was extremely helpful, and gave me an insight into the bones of the trade.
I'm under no illusions about how hard it is to scrape a living, chasing invoices etc, but I really do dream of setting my own agenda and having freedom to pursue my own interests.

Any help would be much appreciated...
...should I develop a specialism or aim to stay as broad as possible?
...is it worth building relationships with trade etc mags before approaching mainstream print media?
...where do you make most of your money?
...how much of a run-up should I give myself before handing in notice?

Thanks for reading, any input would be gratefully received....